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Electrical discharge-assisted milling (EDAM) is an efficient method for processing titanium alloys, but the processing mechanism of EDAM titanium alloy is not completely understood. Therefore, in this study, a thermal-mechanical coupling cutting model was established to examine the processing mechanism of EDAM. The thermal-mechanical coupling model included a random discharge model and a cutting model with a temperature field. The temperature field of the workpiece after discharge and before cutting was clarified. Based on the high-temperature hardness test results of the titanium alloy and modified layer after discharge, increasing the temperature can effectively reduce their material hardness. In addition, the material removal process and chip formation mechanism in EDAM and conventional milling (CM) were studied. The variation laws of the cutting force, stress, and cutting temperature under two cutting methods are discussed. A verification experiment showed that the cutting force was in good agreement with the simulation results. Moreover, EDAM can effectively reduce the cutting force, as well as the stress distribution on the surface of the workpiece. These results can provide an important reference for EDAM to formulate the machining parameters.

In this paper, new tethered aerial robots including roaming tethered aerial robots (RTARs) for radioactive material sampling and stationary tethered aerial robots (STARs) for environment monitoring are proposed to meet extremely-long-endurance missions of nuclear power plants. The flight of the proposed tethered aerial robots may last for a few days or even a few months as long as the tethered cable provides continuous power. A high voltage AC or DC power system was newly adopted to reduce the mass of the tethered cable. The RTAR uses a tethered cable spooled from the aerial robot and an aerial tension control system. The aerial tension control system provides the appropriate tension to the tethered cable, which is accordingly laid down on the ground as the RTAR roams. The STAR includes a tethered cable spooled from the ground and a ground tension control system, which enables the STAR to reach high altitudes. Prototypes of the RTAR and STAR were designed and successfully demonstrated in outdoor environments, where the load power, power type, operating frequency, and flight attitude of the RTAR and STAR were: 180 W, AC 100 kHz, and 20 m; and 300 W, AC or DC 100 kHz, and 80 m, respectively.

The objective of voluntary disclosure regulation is to mitigate information asymmetry between the management and outside users. However, prior studies on voluntary disclosures provide mixed evidences on managers’ incentives. Using a setting of voluntary non-generally accepted accounting principles earnings per share (GAAP EPS) reporting, this study attempts to examine whether the first non-GAAP EPS reporting is less dominated by opportunistic incentives. Consistent with the predictions of this research, it reveals that the duration to the first adjusted EPS disclosure is not more sensitive to negative transitory items, and moreover investors’ perception on the first non-GAAP EPS is more positive compared to subsequent ones. The less opportunistic behaviour on the first disclosure can be well explained by the management’s awareness of intensified monitoring by outside stakeholders.

This paper presents a method to derive the theoretical requirements for the development of a 400 mm optical window that transmits dual-band wavelengths and had a stable structure. We also present design and fabrication results. Among the required specifications, the surface figure error was defined by the transmitted wavefront deformation (TWD), λ/15 rms at 632.8 nm. This value was derived by estimating the predicted performances with respect to five independent items that could cause system performance degradation and then calculating the required wavefront error (WFE) to satisfy the performance goals. We measured the image resolution at each performance level to trace and verify the requirements. The article also describes a design optimization process that could minimize the weight and volume of the optical window attached to the payload securing the FOV of the camera. In addition, we accurately measured the deformation that occurred in the series of fabrication steps including processing, coating, assembly, bonding and bolting, and investigated the effects by comparing them to the results of a simulation performed in advance to derive the predicted performance.

The vergence control of binocular stereoscopic camera is the most essential factor for acquiring high quality stereoscopic images. In this paper, we proposed a binocular stereoscopic camera vergence control method using disparity information by the simple image processing and estimate the quantity of vergence control using the Lagrange interpolation equation. The method of extracting disparity information through image processing is as follows: first the key-object in left & right images was extracted through labeling of the central area of the image, and then a simple method was used for calculating the disparity value of the same key-object in the labeled left and right images. The vergence control method uses disparity information and keeps the convergence distance of left & right cameras and the distance of the key-object the same. According to the proposed method, variance in the distance of the key-object and application of calculated disparity information of obtained left & right images to the quadratic Lagrange interpolation equation could estimate the quantity of vergence control, which confirmed that the method of stereoscopic camera vergence control can be simplified through experiments on various key-objects and other convergence distance.

This paper describes an integrated tunneling sensor for applications of an electronic nose and a scanning probe microscope. Ultra-thin silicon dioxide having a thickness of ~2 nm is used as a material of the tunneling sensor. It provides much higher sensitivity in comparison with others sensing methods. The tunneling sensor is placed on a fixed edge where the maximum strain arises. As additional masses or forces are added to the surface of the cantilever, the thickness of the thin silicon dioxide layer is slightly decreased. By using exponential nature of electron tunneling dominated by the thickness of the silicon dioxide it can be used as an ultra-high sensitive sensor. The thin dioxide is fabricated by dry oxidation using a vertical furnace. The cantilever structures are defined by conventional MEMS technologies. Current density of the tunneling sensor is evaluated as a function of voltage and is compared with numerical analysis based on direct tunneling phenomena.

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The parallel stereoscopic camera has a linear relationship between vergence and focus control. We introduced the automatic control method for a stereoscopic camera system that uses the relationship between vergence and focus of a parallel stereoscopic camera. The automatic control method uses disparity compensation of the acquired image pair from the stereoscopic camera. For faster extraction of disparity information, the proposed binocular disparity estimation method by the one-dimensional cepstral filter algorithm would be investigated. The suggested system in this study greatly reduces the extraction time requirement and error so as to offer spontaneous control and greater real-time realism to acquire high quality stereoscopic images. © 2004 SPIE and IS&T.

Horizontally-moving method (HMM) stereoscopic camera has a liner relationship between ver-gence and focus control. We introduced the automatic control method for a stereoscopic camera system that uses the relationship between vergence and focus of an HMM stereoscopic camera. the Automatic control method uses disparity compensation of the acquired image pair from the stereoscopic camera. For faster extraction of disparity information, the proposed binocular dispar-ity estimation method by the one-dimensional cepstral filter algorithm would be investigated. The suggested system in this study substantially reduced the controlling time and error-ratio so as to make it possible to achieve natural and clear images.

Measurements of the saturated transmission and the undepleted ground-state population density of both Cr^4+:YAG crystals and dye films as saturable absorbers have been experimentally attempted to understand the additional unsaturated losses in a high Q state. The saturated transmission of a saturable absorber is less than its maximum at a high saturation fluence because of the undepleted ground-state population density. Higher saturated transmission and lower undepleted ground-state population density have been observed for Cr^4+:YAG crystals than have been observed for dye films at high optical densities.

The threshold pump energies at 1.06 µm and Raman gain coefficients of stimulated Raman scattering (SRS) at 1.54 µm have been measured in both single-pass and half-resonator configurations at various methane pressures. In the single-pass configuration, the Raman gain coefficients of the backward and forward SRS are 0.32 and 0.23 cm/GW at 95 atm, respectively. The backward Raman gain coefficient is higher than the forward Raman gain coefficient. This gain reduction is caused by the depletion of local pump intensity, the phase-matching conditions, and the transient effect of the high amplification rate in the forward SRS process. In the half-resonator configuration, the Raman gain coefficient was 0.46 cm/GW at 75 atm of methane.

Three‐dimensional printing (3DP) technology has attracted interest in various fields of applications. However, most of the previous studies are focusing on additive printing or developing new printable materials to functionalize the printed structures. Those approaches obviously have shown great performance, but still have no solution to functionalize original printing materials that are supplied by printer suppliers. In this study, we report a feasible method to fabricate three‐dimensional printed micro‐containers (MCs) coated with Ni‐Au core‐shell nanowires (NWs) that have multifunctional properties. The surfaces of the polymer‐based micro‐containers are modified with thiol groups. Then Ni‐Au nanowires are directly attached without further treatment. Our approach expands direct applications of polymeric 3DP materials to biomedical and pharmaceutical technology as a utilized platform for functional nanostructures.